This invention is related to a device for cutting small to large sized and reinforced rubberized tubing. More particularly, the invention deals with such a device functioning both as a hand held and a bench top tool. Some applications are the cutting of radiator hoses in an automotive repair shop or the cutting of certain plastic tubing for plumbing work.
The need of thus the existence of prior art and associated devices for cutting a variety of tubing has been around for many years. For example, both Canadian Patent No. 1,178,426 and U.S. Pat. No. 5,987,750 disclosed a scissors type of tube cutter including two arms connected in their middle points and operating with a scissors like action. One end of the arms consists of a pair of opposing jaws. One of the jaws has a tube-shaped support surface that positions a tube for engagement by a blade held by the other jaw. Both of the disclosed devices have been commercialized and have been useful in cutting reinforced rubberized tubes. However, the manufacturers of these two devices typically limit the outside diameter of tubes to be cut to 1.5xe2x80x3 or smaller (Lisle Catalog 2000, page 50; S and G Tool Aid Catalog, page 41; Snap On Catalog 2000, page E-33; Mac Tool Catalog 2000, Page 310; Matco Catalog 1998-1999, page 182). These devices are not useful in cutting reinforced radiator hoses of larger sizes from 2xe2x80x3 to 2.5xe2x80x3 in outside diameter. This inventor has experimented with an enlarged version of the scissors design as mentioned above and has found four major limitations of such a design for cutting large sized tubes:
1. The cutting device has to be 24xe2x80x3 or longer in order to achieve enough leverage to cut a tough reinforced radiator tube of diameter in the range of 2xe2x80x3-2.75xe2x80x3. Thus, it is too large to be of practical use for an auto mechanic.
2. While these devices all use a sharp pointed blade thus having a very small contact area for the penetration and cutting of a reinforced tube, some of the larger sized radiator hoses are much more flexible than the smaller ones. Thus, the surface deformation of the larger sized radiator hoses results in a large area of contact with the blade. Consequently, the larger sized radiator hoses still make the cutting more difficult.
3. When cutting a hose near its end, the surface near the end is less rigid thus it flexes more than the surface of the longer portion of the hose. The uneven flexing of the hose straddling the blade tends to force the blade thus the device to bend toward the side that flexes less (the longer side of the hose). As a consequence, the bent blade either fails to cut properly or can not cut at all.
4. Yet another draw back of the large scissors design is that it has to be operated by two hands. Consequently, an operator does not have a spare hand to hold the hose in proper position to be cut.
U.S. Pat. No. 4,412,380 (Kish, 1983) discloses a cutter for air conditioning hoses. The device comprises a base that is provided with axially spaced and axially aligned tubes for the reception of the hose to be cut. The device further consists of a manually operable handle that is pivotally secured to the base and a cutter blade that is movable through the hose to sever the hose into a desired length. As such, the device is designed toward an application wherein it is to be mounted on the top of a workbench, not a portable tool. It can not be easily used as a convenient hand held tool. Furthermore, the device employs an axially spaced and axially aligned tube to hold the hose to be cut. Therefore, the size of the holding tube needs to be fairly close to that of the hose to be cut. As the holding tube is an integral part of the device, a user needs to maintain several cutters having different sized holding tubes to cover a wide range of hose sizes. This is rather expensive and inconvenient.
In light of the various drawbacks of the prior art as explained above, the present invention is directed to an improved hose cutter.
It is an objective of this invention to devise a compact, portable and hand held hose cutter that is small enough to be stored in a mechanic""s tool box.
The second objective of this invention is to have the subject hose cutter capable of cutting a large sized radiator hose as well as smaller sized tubes or hoses.
The third objective of this invention is to make the subject hose cutter also functional as a bench top or floor model, whereby an operator would operate the cutter with one hand while holding the hose to be cut with another hand.
Other objectives, together with the foregoing are also attained in the exercise of the invention as described in the following description and resulting in the embodiment illustrated in the accompanying drawings.